1. Field of the Invention
The present invention relates to a method and apparatus for reading a pattern image, such as a two-dimensional barcode pattern image or the like, and a program for reading a pattern image.
2. Description of the Related Art
In recent years, barcodes have come into wide use in the fields of distribution, manufacturing, logistics, service, and the like. Two-dimensional barcodes, such as QR Code® and the like, which are obtained by two-dimensionally expanding a one-dimensional barcode (bars are arranged in only one direction) also increasingly spread.
Advancement of an optical reading apparatus stimulates the appearance of the standard with a high recording density. Though depending on the standard, the one-dimensional barcode can express around 20 alphanumeric characters. In recent years, the standard regarding a two-dimensional barcode capable of storing information of more than 2000 characters has appeared.
Most mobile phone terminals which have rapidly spread have a camera mounted therein. An application has also come into use which can automatically acquire a mail address or the URL (Uniform Resource Locator) of a Web site when a two-dimensional barcode displayed on an advertising medium is photographed by the camera of the mobile phone terminal.
The barcodes are not all displayed on paper mediums. The pattern image of a barcode posted on a Web page may be displayed on a display screen and captured by the camera of the mobile phone terminal so as to acquire URL information.
While a communication apparatus, such as a mobile phone terminal or the like, can simply acquire information from, for example, an advertising medium or the like by using a barcode, unlike typical data communication, the amount of information is limited due to the optical limitation. At present, character information of not more than about 2000 characters can be presented. This is because, even though the recording density of the barcode patterns simply increases, the camera mounted in a communication apparatus, such as a mobile phone terminal or the like, has a limited resolution, so the amount of information to be imported is limited.
As described above, according to the related art, information can be easily presented by the barcode, but the limited amount of information can merely be presented.
A method of increasing the amount of information to be presented by a barcode is described in Japanese Unexamined Patent Application Publication No. 2007-156969. The barcode presentation method described in Japanese Unexamined Patent Application Publication No. 2007-156969 is applied to the pattern image of a barcode displayed on a display screen. According to this method, the pattern image of the barcode is not displayed in the form of a still image, but the pattern image of the barcode is configured such that multiple sheets (multiple pages) are displayed and presented successively in a temporal direction, like a motion image.
According to the method described in Japanese Unexamined Patent Application Publication No. 2007-156969, information can be presented by a barcode pattern group having multiple pages and therefore a large amount of information can be presented.